P69786 · PTGCB_ECOLI
- ProteinPTS system glucose-specific EIICB component
- GeneptsG
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids477 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score5/5
Function
function
The phosphoenolpyruvate-dependent sugar phosphotransferase system (sugar PTS), a major carbohydrate active transport system, catalyzes the phosphorylation of incoming sugar substrates concomitantly with their translocation across the cell membrane. The enzyme II complex composed of PtsG and Crr is involved in glucose transport (PubMed:10562420, PubMed:3129430).
Also functions as a chemoreceptor monitoring the environment for changes in sugar concentration and an effector modulating the activity of the transcriptional repressor Mlc (PubMed:18319344).
In the presence of glucose in the medium, the dephosphorylated form of PtsG can interact with Mlc, leading to sequestration of Mlc in the inner membrane and inhibition of its repressor activity (PubMed:11032803, PubMed:11157755, PubMed:12529317, PubMed:18319344).
Also functions as a chemoreceptor monitoring the environment for changes in sugar concentration and an effector modulating the activity of the transcriptional repressor Mlc (PubMed:18319344).
In the presence of glucose in the medium, the dephosphorylated form of PtsG can interact with Mlc, leading to sequestration of Mlc in the inner membrane and inhibition of its repressor activity (PubMed:11032803, PubMed:11157755, PubMed:12529317, PubMed:18319344).
(Microbial infection) Probably transports the toxic C-terminal region of CdiA from E.coli strains NC101 and 3006 across the inner membrane to the cytoplasm, where CdiA degrades specific tRNAs. Toxin transport is strain-specific, mutations in this gene do not confer resistance to several other tested CdiA toxins (PubMed:26305955).
Probably also serves as the inner membrane receptor for CdiA-STECO31 from E.coli strain STEC_O31 (Probable)
Probably also serves as the inner membrane receptor for CdiA-STECO31 from E.coli strain STEC_O31 (Probable)
Catalytic activity
- D-glucose(out) + N(pros)-phospho-L-histidyl-[protein] = D-glucose 6-phosphate(in) + L-histidyl-[protein]
Activity regulation
Transporter activity may be inhibited by SgrT.
Features
Showing features for active site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Active site | 421 | Phosphocysteine intermediate; for EIIB activity | ||||
Sequence: C |
GO annotations
Aspect | Term | |
---|---|---|
Cellular Component | membrane | |
Cellular Component | plasma membrane | |
Cellular Component | transmembrane transporter complex | |
Molecular Function | glucose transmembrane transporter activity | |
Molecular Function | kinase activity | |
Molecular Function | protein-N(PI)-phosphohistidine-sugar phosphotransferase activity | |
Molecular Function | protein-phosphocysteine-glucose phosphotransferase system transporter activity | |
Biological Process | glucose import across plasma membrane | |
Biological Process | glucose transmembrane transport | |
Biological Process | phosphoenolpyruvate-dependent sugar phosphotransferase system | |
Biological Process | regulation of DNA-templated transcription |
Keywords
- Molecular function
- Biological process
Enzyme and pathway databases
Protein family/group databases
Names & Taxonomy
Protein names
- Recommended namePTS system glucose-specific EIICB component
- Alternative names
Including 2 domains:
- Recommended nameGlucose permease IIC component
- Alternative names
- Recommended nameGlucose-specific phosphotransferase enzyme IIB component
- EC number
- Alternative names
Gene names
Organism names
- Organism
- Strains
- Taxonomic lineageBacteria > Pseudomonadota > Gammaproteobacteria > Enterobacterales > Enterobacteriaceae > Escherichia
Accessions
- Primary accessionP69786
- Secondary accessions
Proteomes
Subcellular Location
UniProt Annotation
GO Annotation
Cell inner membrane ; Multi-pass membrane protein
Features
Showing features for topological domain, transmembrane.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Topological domain | 1-14 | Cytoplasmic | ||||
Sequence: MFKNAFANLQKVGK | ||||||
Transmembrane | 15-35 | Helical | ||||
Sequence: SLMLPVSVLPIAGILLGVGSA | ||||||
Topological domain | 36-50 | Periplasmic | ||||
Sequence: NFSWLPAVVSHVMAE | ||||||
Transmembrane | 51-71 | Helical | ||||
Sequence: AGGSVFANMPLIFAIGVALGF | ||||||
Topological domain | 72-79 | Cytoplasmic | ||||
Sequence: TNNDGVSA | ||||||
Transmembrane | 80-100 | Helical | ||||
Sequence: LAAVVAYGIMVKTMAVVAPLV | ||||||
Topological domain | 101-111 | Periplasmic | ||||
Sequence: LHLPAEEIASK | ||||||
Transmembrane | 112-132 | Helical | ||||
Sequence: HLADTGVLGGIISGAIAAYMF | ||||||
Topological domain | 133-151 | Cytoplasmic | ||||
Sequence: NRFYRIKLPEYLGFFAGKR | ||||||
Transmembrane | 152-172 | Helical | ||||
Sequence: FVPIISGLAAIFTGVVLSFIW | ||||||
Topological domain | 173-190 | Periplasmic | ||||
Sequence: PPIGSAIQTFSQWAAYQN | ||||||
Transmembrane | 191-211 | Helical | ||||
Sequence: PVVAFGIYGFIERCLVPFGLH | ||||||
Topological domain | 212-249 | Cytoplasmic | ||||
Sequence: HIWNVPFQMQIGEYTNAAGQVFHGDIPRYMAGDPTAGK | ||||||
Transmembrane | 250-270 | Helical | ||||
Sequence: LSGGFLFKMYGLPAAAIAIWH | ||||||
Topological domain | 271-279 | Periplasmic | ||||
Sequence: SAKPENRAK | ||||||
Transmembrane | 280-300 | Helical | ||||
Sequence: VGGIMISAALTSFLTGITEPI | ||||||
Topological domain | 301-309 | Cytoplasmic | ||||
Sequence: EFSFMFVAP | ||||||
Transmembrane | 310-330 | Helical | ||||
Sequence: ILYIIHAILAGLAFPICILLG | ||||||
Topological domain | 331-355 | Periplasmic | ||||
Sequence: MRDGTSFSHGLIDFIVLSGNSSKLW | ||||||
Transmembrane | 356-376 | Helical | ||||
Sequence: LFPIVGIGYAIVYYTIFRVLI | ||||||
Topological domain | 377-477 | Cytoplasmic | ||||
Sequence: KALDLKTPGREDATEDAKATGTSEMAPALVAAFGGKENITNLDACITRLRVSVADVSKVDQAGLKKLGAAGVVVAGSGVQAIFGTKSDNLKTEMDEYIRNH |
Keywords
- Cellular component
Phenotypes & Variants
Disruption phenotype
Disruption confers resistance to cellular contact-dependent growth inhibition (CDI) CdiA of E.coli strains NC101 and 3006, but not to several other tested CdiA toxins (PubMed:26305955).
Disruption confers resistance to cellular contact-dependent growth inhibition (CDI) CdiA-STECO31 of E.coli strain STEC_O31 (PubMed:28351921).
Disruption confers resistance to cellular contact-dependent growth inhibition (CDI) CdiA-STECO31 of E.coli strain STEC_O31 (PubMed:28351921).
Features
Showing features for mutagenesis.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Mutagenesis | 204 | Destabilizes the protein structure; when associated with S-326. | ||||
Sequence: C → S | ||||||
Mutagenesis | 326 | Destabilizes the protein structure; when associated with S-204. | ||||
Sequence: C → S | ||||||
Mutagenesis | 419 | Still allows binding to Mlc. | ||||
Sequence: D → A | ||||||
Mutagenesis | 421 | Still allows binding to Mlc. Derepression of Mlc targets becomes constitutive, i.e. independent of PTS phosphorylation. | ||||
Sequence: C → D | ||||||
Mutagenesis | 421 | Unable to be phosphorylated and to catalyze the phosphoryl exchange between glucose and glucose 6-phosphate at equilibrium. Remains susceptible to CdiA toxin from E.coli strain 3006. Still allows binding to Mlc. Derepression of Mlc targets becomes constitutive, i.e. independent of PTS phosphorylation. | ||||
Sequence: C → S | ||||||
Mutagenesis | 422 | Still allows binding to Mlc. | ||||
Sequence: I → A | ||||||
Mutagenesis | 423 | Decreases Mlc binding. | ||||
Sequence: T → A | ||||||
Mutagenesis | 424 | Cannot bind Mlc. Destroys the ability of Cys-421 to be phosphorylated in vitro. | ||||
Sequence: R → A or H | ||||||
Mutagenesis | 424 | Cannot bind Mlc. Cys-421 can be phosphorylated in vitro. | ||||
Sequence: R → K | ||||||
Mutagenesis | 426 | Still allows binding to Mlc. Cys-421 is weakly phosphorylated in vitro. | ||||
Sequence: R → A | ||||||
Mutagenesis | 449 | Interaction with Mlc is hardly detectable. | ||||
Sequence: V → Q | ||||||
Mutagenesis | 451 | The complex with Mlc shows much weaker association than the wild-type. | ||||
Sequence: A → F | ||||||
Mutagenesis | 456 | Decreases Mlc binding. Interaction with Mlc is hardly detectable. | ||||
Sequence: Q → A | ||||||
Mutagenesis | 458 | Still allows binding to Mlc. | ||||
Sequence: I → A |
PTM/Processing
Features
Showing features for chain, modified residue.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000186528 | 1-477 | PTS system glucose-specific EIICB component | |||
Sequence: MFKNAFANLQKVGKSLMLPVSVLPIAGILLGVGSANFSWLPAVVSHVMAEAGGSVFANMPLIFAIGVALGFTNNDGVSALAAVVAYGIMVKTMAVVAPLVLHLPAEEIASKHLADTGVLGGIISGAIAAYMFNRFYRIKLPEYLGFFAGKRFVPIISGLAAIFTGVVLSFIWPPIGSAIQTFSQWAAYQNPVVAFGIYGFIERCLVPFGLHHIWNVPFQMQIGEYTNAAGQVFHGDIPRYMAGDPTAGKLSGGFLFKMYGLPAAAIAIWHSAKPENRAKVGGIMISAALTSFLTGITEPIEFSFMFVAPILYIIHAILAGLAFPICILLGMRDGTSFSHGLIDFIVLSGNSSKLWLFPIVGIGYAIVYYTIFRVLIKALDLKTPGREDATEDAKATGTSEMAPALVAAFGGKENITNLDACITRLRVSVADVSKVDQAGLKKLGAAGVVVAGSGVQAIFGTKSDNLKTEMDEYIRNH | ||||||
Modified residue | 421 | Phosphocysteine | ||||
Sequence: C |
Keywords
- PTM
Proteomic databases
PTM databases
Expression
Induction
Induced by glucose (PubMed:9781886).
Expression is positively regulated by the cAMP-CRP complex and negatively regulated by the Mlc transcriptional repressor (PubMed:9781886).
Mlc and CRP-cAMP bind independently to the ptsG promoter region, and the action of Mlc is dominant over the cAMP-CRP action (PubMed:9781886).
The ptsG transcript is degraded under conditions of glucose-phosphate stress (due to intracellular accumulation of glucose-6-phosphate caused by disruption of glycolytic flux), or in the presence of (toxic) non-metabolizable glucose phosphate analogs due to hybridization with the small RNA sgrS (originally known as ryaA). This hybridization is sufficient to repress mRNA translation. The hybrid is subsequently degraded by RNase E. This reduces the quantity of transporter and relieves glucose phosphate stress (PubMed:15522088, PubMed:16549791).
Expression is positively regulated by the cAMP-CRP complex and negatively regulated by the Mlc transcriptional repressor (PubMed:9781886).
Mlc and CRP-cAMP bind independently to the ptsG promoter region, and the action of Mlc is dominant over the cAMP-CRP action (PubMed:9781886).
The ptsG transcript is degraded under conditions of glucose-phosphate stress (due to intracellular accumulation of glucose-6-phosphate caused by disruption of glycolytic flux), or in the presence of (toxic) non-metabolizable glucose phosphate analogs due to hybridization with the small RNA sgrS (originally known as ryaA). This hybridization is sufficient to repress mRNA translation. The hybrid is subsequently degraded by RNase E. This reduces the quantity of transporter and relieves glucose phosphate stress (PubMed:15522088, PubMed:16549791).
Interaction
Subunit
Homodimer (Probable) (PubMed:10562420, PubMed:12716891, PubMed:18319344).
The dephosphorylated form interacts with the Mlc transcriptional repressor (PubMed:11032803, PubMed:11157755, PubMed:12529317, PubMed:18319344).
Mlc and the EIIB domain form a complex with the 1:1 stoichiometry (PubMed:18319344).
The dephosphorylated form interacts with the Mlc transcriptional repressor (PubMed:11032803, PubMed:11157755, PubMed:12529317, PubMed:18319344).
Mlc and the EIIB domain form a complex with the 1:1 stoichiometry (PubMed:18319344).
Binary interactions
Type | Entry 1 | Entry 2 | Number of experiments | Intact | |
---|---|---|---|---|---|
BINARY | P69786 | mlc P50456 | 3 | EBI-903497, EBI-1116104 |
Protein-protein interaction databases
Structure
Family & Domains
Features
Showing features for domain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Domain | 1-388 | PTS EIIC type-1 | ||||
Sequence: MFKNAFANLQKVGKSLMLPVSVLPIAGILLGVGSANFSWLPAVVSHVMAEAGGSVFANMPLIFAIGVALGFTNNDGVSALAAVVAYGIMVKTMAVVAPLVLHLPAEEIASKHLADTGVLGGIISGAIAAYMFNRFYRIKLPEYLGFFAGKRFVPIISGLAAIFTGVVLSFIWPPIGSAIQTFSQWAAYQNPVVAFGIYGFIERCLVPFGLHHIWNVPFQMQIGEYTNAAGQVFHGDIPRYMAGDPTAGKLSGGFLFKMYGLPAAAIAIWHSAKPENRAKVGGIMISAALTSFLTGITEPIEFSFMFVAPILYIIHAILAGLAFPICILLGMRDGTSFSHGLIDFIVLSGNSSKLWLFPIVGIGYAIVYYTIFRVLIKALDLKTPGRED | ||||||
Domain | 399-477 | PTS EIIB type-1 | ||||
Sequence: SEMAPALVAAFGGKENITNLDACITRLRVSVADVSKVDQAGLKKLGAAGVVVAGSGVQAIFGTKSDNLKTEMDEYIRNH |
Domain
The EIIB domain is phosphorylated by phospho-EIIA on a cysteinyl or histidyl residue, depending on the transported sugar. Then, it transfers the phosphoryl group to the sugar substrate concomitantly with the sugar uptake processed by the EIIC domain.
The EIIC domain forms the PTS system translocation channel and contains the specific substrate-binding site.
Initial studies suggest that binding to Mlc requires the EIIB domain and the EIIC-B junction region, or that the soluble EIIB domain is sufficient (PubMed:11032803, PubMed:11157755).
A more recent study shows that the soluble EIIB domain is sufficient to interact with Mlc but only when EIIB is attached to the membrane by a protein anchor (PubMed:12529317).
A more recent study shows that the soluble EIIB domain is sufficient to interact with Mlc but only when EIIB is attached to the membrane by a protein anchor (PubMed:12529317).
Keywords
- Domain
Phylogenomic databases
Family and domain databases
Sequence
- Sequence statusComplete
- Length477
- Mass (Da)50,677
- Last updated1987-08-13 v1
- ChecksumD97A80FD64B74F73
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
J02618 EMBL· GenBank· DDBJ | AAA24437.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
U00096 EMBL· GenBank· DDBJ | AAC74185.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
AP009048 EMBL· GenBank· DDBJ | BAA35908.1 EMBL· GenBank· DDBJ | Genomic DNA |